Skip NAs when aggregating with complex dtypes

Author: shoyer

xray/core/ops.py

@@ -292,8 +292,8 @@ def f(values, axis=None, skipna=None, **kwargs):
         if coerce_strings and values.dtype.kind in 'SU':
             values = values.astype(object)
 
-        if skipna or (skipna is None and values.dtype.kind == 'f'):
-            if values.dtype.kind not in ['i', 'f']:
+        if skipna or (skipna is None and values.dtype.kind in 'cf'):
+            if values.dtype.kind not in ['i', 'f', 'c']:
                 raise NotImplementedError(
                     'skipna=True not yet implemented for %s with dtype %s'
                     % (name, values.dtype))

xray/test/test_variable.py

@@ -382,6 +382,12 @@ def test_real_and_imag(self):
         expected_abs = self.cls('x', np.sqrt(2 * np.arange(3) ** 2))
         self.assertVariableAllClose(abs(v), expected_abs)
 
+    def test_aggregate_complex(self):
+        # should skip NaNs
+        v = self.cls('x', [1, 2j, np.nan])
+        expected = Variable((), 0.5 + 1j)
+        self.assertVariableAllClose(v.mean(), expected)
+
 
 class TestVariable(TestCase, VariableSubclassTestCases):
     cls = staticmethod(Variable)